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Informational Letter IL 84-6

TO: All Energy Operators

MINED OIL SANDS BITUMEN PROCESSING TECHNOLOGY

INTRODUCTION

In accordance with its obligations to ensure orderly, efficient development of energy resources in Alberta consistent with sound environmental protection, the Alberta Energy Resources Conservation Board (ERCB) has stressed the need for improved extraction and upgrading technology for the processing of mined oil sands *(1,2,3,4) . Also, the ERCB recognized that a considerable lead time would have to be provided between basic laboratory research and field demonstration testing and the anticipated time of commercial implementation in future mined oil sands projects.

This informational letter pertains to the above subject matter and specifically is for the purpose of announcing the release of a report entitled "Oil Sands Bitumen Extraction Process Evaluation" prepared by Dynawest Projects Ltd. for the ERCB.

BOARD OBJECTIVES

In the Board's view, the desirable target for crude bitumen extraction efficiency from mined ore would be 95 per cent by mass or higher. Operating experience at the two existing plants, Suncor and Syncrude, has generally confirmed that the Clark hot water process when applied to ore grades below 10 per cent bitumen by mass results in recoveries less than 90 per cent by mass. The result is not only lower than desirable bitumen recovery, but also tailings accumulation rates disproportionately larger than for the higher grade ores.

This experience, along with a knowledge of the relationship between fresh water requirements and extraction efficiency, has convinced the Board that a process which could consistently achieve 95 per cent by mass or greater extraction efficiency would simultaneously enhance bitumen recovery, improve environmental management, and probably increase economic returns. *(5,6)

DYNAWEST BITUMEN EXTRACTION PROCESS EVALUATION

With those potential benefits in mind, the Board has continued to prompt investigation and demonstration of improved extraction technology. Its most recent endeavour in this regard is release of a report prepared by Dynawest Projects Ltd. The report describes and presents results of investigations which commenced some two years ago under the direction of the ERCB Management Committee chaired by Dr. R. N. Houlihan.

The ERCB retained Dynawest to undertake a detailed investigation of promising extraction processes and the potential timing of their commercial implementation. The study was executed in three stages: a general review to identify potential improved extraction techniques, a preliminary appraisal of more advanced processes, and detailed study of selected processes. In the initial stage, Dynawest conducted a general review of published and patented bitumen extraction technology and identified 33 processes for consideration. Processes not being actively developed or for which data were not available were rejected after initial evaluation. For the remaining processes, data were obtained from developers, a technical evaluation was undertaken and each process was checked against screening criteria. The list of processes was screened to eleven which appeared to have potential and were supported by laboratory or field demonstration testing and also met certain criteria including: tested on Athabasca bituminous sands, ability to process low grade ore, improved hydrocarbon recovery and energy efficiency, potential to reduce environmental impact, potential for scale-up, and detailed material and energy balance data support. The detailed study included an assessment of the potential for technical and economic merit of the selected processes and requirements and proximity of commercial application.

The final draft report was reviewed on a confidential basis by an external review panel,*(7) composed of knowledgeable persons primarily from the oil sands industry, who provided valuable input and made recommendations for further work. It was the concensus of the review panel that the report was a valuable assessment of extraction technology and that some investigations should be extended using a collaborative industry approach. Certain limitations of the detailed study were also pointed out including such issues as inter-relationship of the utilities plant and process facilities, limited examination of modified hot water processes, and only preliminary review of solvent processes. However, the review panel recommended that major modifications to the study be left to a subsequent study.

ABSTRACT

The study evaluated alternative processes for extraction of bitumen from mined oil sands. A preliminary technical evaluation of possible processes was first undertaken and then selected processes were subjected to detailed evaluation.

The first phase of the study involved an evaluation of each alternative process against a base case hot water extraction process. Material balance and energy efficiency calculations were made for a medium grade Athabasca bituminous sand (10 per cent bitumen by mass). Consideration was given to the proven ability of processes to increase resource recovery and energy efficiency and to reduce environmental problems compared to the base case. The future commercial and scale-up potential for the processes were also assessed.

The first phase resulted in the identification of seven alternatives to be considered for detailed study of which three were subjected to detailed investigation. These alternatives and the base case are listed below by process type:

• Hot Water Extraction - Base Case
• Modified Hot Water Extraction
  • Two Stage Flotation Process
  • RTR Process
• Direct Retorting
  • Taciuk Process
  • Lurgi Process
• Solvent Extraction
  • SESA Process
  • Dravo Process
• Oleophilic Sieve - Kruyer Process

Although all of the processes identified in the first phase were of keen interest to the ERCB, budget limitations forced it to limit detailed evaluation to four cases only. Thus, the second phase consisted of a detailed comparative evaluation of the following four selected processes:

• Hot Water Extraction - Base Case
• Modified Hot Water Extraction - Two Stage Flotation Process
  (Developer: Syncrude Canada Ltd.)
• Direct Retorting - Taciuk Process
  (Developer: UMATAC Industrial Processes Ltd.)
• Oleophilic Sieve - Kruyer Process
  (Developer: Oleophilic Sieve Development of Canada Ltd.,
  Kruyer Research and Development Ltd., and
  J. Kruyer Oil Corporation)

Each process was compared with the base case to determine the relative technical and economic advantages and disadvantages of the processes. A direct comparison of alternative processes was not attempted nor would it be feasible as each process is at a significantly different level of development for actual commercial operations.

A commercial design was conceptualized and evaluated for each process. The design was broadly based on the proposed Alsands Project, corresponding to an upgrader feed rate of some 25 000 cubic metres per calendar day of upgrader bitumen.

Of the processes studied, the Taciuk Process is considered to have the best long-term potential. The development of this promising process would depend on successful scale-up, which would have to be proven by field demonstration.

The Two Stage Flotation Process, a proprietary technology held by the Syncrude consortium, uses mainly conventional technology, and would require a short time frame for commercialization. The commercial development of this process would be of relatively low risk but would require successful demonstration of equipment scale-up and confirmation that the process can achieve high recovery from low grade ore.

Tailings disposal requirements for all of the alternative processes remain largely unproven. Tailings disposal costs represent a significant initial capital cost, similar to that for the extraction plant itself, and operating costs are also high. Although tailings transportation has been investigated *(8), further study including research and development in this area seems necessary.

Among the alternative processes that were not for budget reasons brought forward to the second phase, the following may be noted: the RTR process has been evaluated at a demonstration plant at the Suncor site and detailed results have been filed with the ERCB under confidential retention rules. Some limited off-site testing on Athabasca bituminous sands has been conducted by Lurgi, but this was not done under ERCB approval and no information has been filed with the ERCB. Laboratory bench scale testing of the SESA and Dravo processes has been performed and in the course of the Dynawest study some of this information was reviewed on a confidential basis. As in the case of the Lurgi work, however, most of this work has been performed outside of Alberta and the ERCB did not have the opportunity to monitor it.

Copies of the final public report on the study may be obtained at a cost of $50.00 from the Maps and Publications Counter (ERCB), 640 - 5 Avenue S.W., Calgary, Alberta, telephone 297 - 8328. The report may also be viewed at the ERCB Library.

Any questions regarding this matter should be directed to the ERCB's Oil Sands Department at 297-3235.

[Original signed by]

N. A. Strom
Board Member

1. "In the Matter of an Application of Shell Canada Ltd. and Shell Exploration Ltd., under Part 8 of the Oil and Gas Conservation Act", ERCB Report 74-H.
2. "In the Matter of an Application of Petrofina Canada Ltd., Pacific Petroleum Ltd., Hudson's Bay Oil and Gas Company Ltd., Murphy Oil Co. Ltd., and Candel Oil Ltd., under Part 8 of the Oil and Gas Conservation Act", ERCB Report 74-X.
3. "In the Matter of an Application of Home Oil Co. Ltd. and Alminex Ltd. under Part 8 of the Oil and Gas Conservation Act", ERCB Report 75-H.
4. "Alsands Fort McMurray Project", ERCB Report 79-H.
5. "Bitumen Resources of Alberta: Converting Resources to Reserves", N. A. Strom and R. B. Dunbar. The Future of Heavy Crude and Tar Sands, McGraw-Hill Inc., 1981.
6. "Bitumen Resources of Alberta: Recover and Conversion to Synthetic Oil Supply", N. Strom, R. B. Dunbar and F. J. Mink, Petroleum Society of CIM, Paper No. 80-31-08, May 1980.
7. The Select Review Panel comprised:
   Dr. M. Cantle, Canstar Oil Sands Ltd.
   Dr. D. W. Devenny, Gulf Canada Resources Inc.
   Mr. D. K. Faurshou, CANMET
   Mr. D. Komery, Shell Canada Resources Ltd.
   Mr. L. C. Stephenson, Esso Resources
   Dr. R. Schutte, Syncrude Canada Ltd.
   Mr. L. R. Turner, AOSTRA
   Mr. I. Webster, Suncor Inc.
8. "Athabasca Oil Sands, Tailings Disposal Beyond Surface Mineable Limits" , A report for the Energy Resources Conservation Board, Alberta Energy and Natural Resources and Alberta Environment, Hardy Associates (1978) Ltd., January 1979.